The neuropeptide galanin has been implicated in a wide range of biological systems: pain transmission, depression/anxiety, memory and feeding behavior. This has resulted in a steady increase in interest in galanin and its functions. However, the role of galanin is neither fully understood in these normal processes nor in pathologies in which it is involved, such as Alzheimer's disease. This proposal provides a tool for the study of its role: a toxin specific for the neurons that are stimulated by galanin. The tool consists of a fusion protein between galanin and the ribosome inactivating protein saporin. The removal of these neurons, and the concomitant changes in behavior, will allow scientists in the above areas of research to study how these neurons participate in each of the behaviors. Because of the different diverse systems that this peptide affects, this tool will be useful to a large number of scientists. Because many, ff not all, of the biological systems utilizing galanin impact drug use and abuse, the tool will result in a greater understanding of those processes also. PROPOSED COMMERCIAL APPLICATIONS: This proposal will result in a commercial reagent for the study of the function of the neuropeptide galanin. The reagent will be used by research scientists who work in the fields of pain, depression/anxiety, pain, drug abuse, memory and feeding. These are topics that are of great interest because of new discoveries in the neurosciences in the last ten years.